#include <stdio.h>
#include <stdlib.h>

int main() {
    int* arr = (int*)calloc(10, 4);
    for (int i = 0; i < 10; i++) {
        arr[i] = i;
    }
    for (int i = 0; i < 10; i++) {
        printf("%d ", arr[i]);
    }
    printf("\n");

    int* arr1 = (int*)realloc(arr, 20 * 4);
    for (int i = 0; i < 20; i++) {
        printf("%d ", arr1[i]);
    }
    printf("\n");

    return 0;
}
